PROCESS FOR PREPARING MAGNESIUM-FERRITE COMPOSITE POWDER USING HYDROTHERMAL SYNTHESIS

摘要

PURPOSE: A process for making mono-dispersive, spherical ultra fine magnesium-ferrite composite powder having spinel crystal structure is provided for magnesium recovery from waste solution containing magnesium ion by using hydrothermal synthesis without calcination process, herein waste solution containing magnesium is leached by acids in the process of tungsten smelting using self-propagating high-temperature synthesis. CONSTITUTION: Fe2+, H2O, and acid waste containing Mg ion are mixed with fixed molar ratios; KOH as pH regulator is added for precipitation of cations to hydroxide salt form, in which dihydric FeCl2 6H2O is used for recovery of magnesium from waste solution; coprecipitates are charged into pressured reactor, hydrothermalized at 130-240C, and then fully washed with hot water for removal of residual cations, then dispersed by ultrasonic washer after addition of methyl alcohol which suppress coagulation of powder, gained by filtration, and then finally vacuum-dried for 24 hours.